Final Conclusion

[400exmxrider15]

I decided to go with:

Wiseco 11:1 Kit (85.50mm)
Polished Exhaust Ports
Bead Blasted cylinder and head


No need to get cylinder studs cause mine are actually brand spankin' new. I was looking through my receipts from when I purchased it from a guy and he said he had receipts for everything, and it said Stud, Bolt (all in different sizes), they were replaced last year in May, so no need to get Heavy Duty....$115 + shipping is a ton of money just for studs. I would pay $100 shipped at tops, but that is even overpriced. Is there anything I can do to my intake port? I've heard of people sharpening that point that flows into the 2 ports. Does that make the fuel atomize quicker???

[tri5ron]

OK,...
Lets try this one more time, with a visit to some of the previous suggestions.
Note,... READ SLOWLY, and give it time to Soak In.

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" We can only give you the advise, knowledge, and personal experiences, that you came here to recieve."

" It's your money.
You can spend it wherever you choose.
Just choose Wise-ly, so that you don't have to choose Twice-ly."

" Remember, the more you research and learn about your machine,...
The more chance you have of holding onto some of your cash.

"Trust us,
The School of Hard Knocks, and College of Experience has a VERY high Tuition."

" A stock chain is ok, but you must understand a CRF chain is MUCH stronger and will stretch and wear out less overtime.

So its always good to do the chain, guides and auto tensioner all at once to be sure everything holds up. Chain stretches, slips a tooth and your gonna have bent valves "

" The reason most do not run higher than 11:1 pistons is b/c of the heat created. The EX doesnt like heat, its air cooled unlike alot of the more recent liquid cooled quads. It generates alot of heat when you up the compression that much and its hard to dissipate the heat.

What are you really looking to get out of it? Keeping up with a 450, being the fastest guy out there? Or just the bragging rights?

In all honesty it sounds to me like you would be much better off buying a 450r. It will have the performance you want, with the liquid cooling-which means you can up the compression quite a bit and still be ok. "

" However, if you dont have the cash to do all the mods it might be a better idea to wait till you have the cash and build it right once and for all. "

" My 400 is also not running as of now, the cylinder has stripped studs, piston is new, but needs re-ringed, i figured while im in the motor, i might as well replace it with a high comp. I dont care for getting a cam right now, I will get a cam after i get done with my suspension (revalved triple rate 450r shocks).. "

" I belive that Density, and Rate of Absorbtion, and directly proportional.
whether they be in Physical, or Comprehensive form. "

[slightlybent47]

Originally posted by tri5ron
OK,...
Lets try this one more time, with a visit to some of the previous suggestions.
Note,... READ SLOWLY, and give it time to Soak In.

----------------------------------------------------------------------------------------------

" We can only give you the advise, knowledge, and personal experiences, that you came here to recieve."

" It's your money.
You can spend it wherever you choose.
Just choose Wise-ly, so that you don't have to choose Twice-ly."

" Remember, the more you research and learn about your machine,...
The more chance you have of holding onto some of your cash.

"Trust us,
The School of Hard Knocks, and College of Experience has a VERY high Tuition."

" A stock chain is ok, but you must understand a CRF chain is MUCH stronger and will stretch and wear out less overtime.

So its always good to do the chain, guides and auto tensioner all at once to be sure everything holds up. Chain stretches, slips a tooth and your gonna have bent valves "

" The reason most do not run higher than 11:1 pistons is b/c of the heat created. The EX doesnt like heat, its air cooled unlike alot of the more recent liquid cooled quads. It generates alot of heat when you up the compression that much and its hard to dissipate the heat.

What are you really looking to get out of it? Keeping up with a 450, being the fastest guy out there? Or just the bragging rights?

In all honesty it sounds to me like you would be much better off buying a 450r. It will have the performance you want, with the liquid cooling-which means you can up the compression quite a bit and still be ok. "

" However, if you dont have the cash to do all the mods it might be a better idea to wait till you have the cash and build it right once and for all. "

" My 400 is also not running as of now, the cylinder has stripped studs, piston is new, but needs re-ringed, i figured while im in the motor, i might as well replace it with a high comp. I dont care for getting a cam right now, I will get a cam after i get done with my suspension (revalved triple rate 450r shocks).. "

" I belive that Density, and Rate of Absorbtion, and directly proportional.
whether they be in Physical, or Comprehensive form. "

So you’re telling him that raising the compression creates to much heat and he should get a 450 instead. Then you tell him you’re raising your compression while you’re in your motor. Sounds to me like "do as I say and not as I do"

[82toyota]

i spent 1580.00 on my topend and i made 39.17hp with 10:5.1 high compression dose not matter really

[hocman123]

why 85.5 i think that like a 402 cc why even spend all that money to get vary little change i would at least go with a 416 and then u would really feel the differance. u could still bore it 2 more times after that if that what u are worryed about

[400exmxrider15]

I still ned to be able to race in a 400 class for MX. Im afraid if I go to a 416, i'm going to have heat problems and i wont be able to race in my same class.

Just a little correction, They aren't stripped cylinder studs, i meant to say stripped valve cover bolts (the 3 right side ones that go down into the cylinder). I love the way my 400 feels now, if I got a 450, it would be brand new off the show room floor.

[hocman123]

if all three of the long bolts are striped then u will have leaking oil on the area that the cam chain rides in trust me i had 2 bad ones and it leaked a good amount

[400exmxrider15]

Originally posted by hocman123
if all three of the long bolts are striped then u will have leaking oil on the area that the cam chain rides in trust me i had 2 bad ones and it leaked a good amount
One of them pulled out while i was riding at a local riding park called Dirty Turtle

[CJM]

Originally posted by 400exmxrider15
One of them pulled out while i was riding at a local riding park called Dirty Turtle

That isnt good, you need to get that fixed otherwise it will leak oil.

[BlasterEaten250]

Originally posted by hocman123
why 85.5 i think that like a 402 cc why even spend all that money to get vary little change i would at least go with a 416 and then u would really feel the differance. u could still bore it 2 more times after that if that what u are worryed about There isn't really a significant power difference between the two if you are running the same compression. And if you bore a stock cylinder to a 440, you are asking for trouble...I would even be afraid to bore to a 426.

[slightlybent47]

Originally posted by 400exmxrider15
I still ned to be able to race in a 400 class for MX. Im afraid if I go to a 416, i'm going to have heat problems and i wont be able to race in my same class.

Just a little correction, They aren't stripped cylinder studs, i meant to say stripped valve cover bolts (the 3 right side ones that go down into the cylinder). I love the way my 400 feels now, if I got a 450, it would be brand new off the show room floor.



I run a 416 with 121/2-1 in this Texas heat and i don't have any heat issues. Just so you know!

[400exmxrider15]

Originally posted by slightlybent47
I run a 416 with 121/2-1 in this Texas heat and i don't have any heat issues. Just so you know!

So you are saying that I'm wasting my time with getting an oil cooler?

[400exmxrider15]

Now you guys have me convinced enough. I'm gonna go ahead listen and go ahead and get GTT HD studs, I'll ship my cylinder out when my mechanic gets it....

[CJM]

Originally posted by 400exmxrider15
Now you guys have me convinced enough. I'm gonna go ahead listen and go ahead and get GTT HD studs, I'll ship my cylinder out when my mechanic gets it.... :p good man, very good.

[400exmxrider15]

Originally posted by CJM
:p good man, very good.

If I go cheap now, it could cause me thousands later....(maybe not that much but quite a bit)

[CJM]

Originally posted by 400exmxrider15
If I go cheap now, it could cause me thousands later....(maybe not that much but quite a bit)

Those studs pull out and your gonna be sorry. Thats why I tell everyone its a good way to spend a few bucks-its not wasted at all.

[400exmxrider15]

Originally posted by CJM
Those studs pull out and your gonna be sorry. Thats why I tell everyone its a good way to spend a few bucks-its not wasted at all.

So expensive to get those studs installed....i really dont wanna spend $115 plus shipping for something that takes a total of 2 hours at most. sounds like someones getting ripped off. Those studs are not even worth $10 a piece, maybe $5, but not $10....I may buy the studs and have my machine shop do it, they are familiar with the Roll formed threads...

[CJM]

So long as your machine shop is confident.

the 50 bucks your spending on them is the fact they mostly cornered the market. The 50 to install them is b/c thats shop rates for an hours worth of work.

[400exmxrider15]

Originally posted by CJM
So long as your machine shop is confident.

the 50 bucks your spending on them is the fact they mostly cornered the market. The 50 to install them is b/c thats shop rates for an hours worth of work.

I guess if I have them do the studs, I might as well have them bore and hone it, but they wont have my piston.....when i talked to my machine shop and they said $67 for bore and hone, $25 glass bead blasting, and $50 for studs.....

[slightlybent47]

Originally posted by 400exmxrider15
So you are saying that I'm wasting my time with getting an oil cooler?


The only thing I did to help with the heat is put on an oversized oil tank, that’s it. The cooler it runs the better. But I have had no issues with heat.
I also kept the stock head studs. If you torque them correctly you should be fine.
If I was to go any bigger then a 416 I would do the head studs. It’s good insurance if you want to go ahead and do them.

I ride mx so most of my riding is at a farley high speed and I do keep it pined most of the time. And when it gets hot say 95 + I can only handle about 45 minuets of hard riding and I’m the one overheating not the bike.lol
That’s not to say that it wouldn’t be overheating in a deferent environment. Say tight woods at low speed or with mud caked on the cooling fins. With the type of riding I do I get good air flow so that helps I’m sure.

[400exmxrider15]

Originally posted by slightlybent47
The only thing I did to help with the heat is put on an oversized oil tank, that’s it. The cooler you can get it the better. But I have had no issues with heat.
I also kept the stock head studs. If you torque them correctly you should be fine.
If I was to go any bigger then a 416 I would do the head studs. It’s good insurance if you want to go ahead and do them.

I ride mx so most of my riding is at a farley high speed and I do keep it pined most of the time. And when it gets hot say 95 + I can only handle about 45 minuets of hard riding and I’m the one overheating not the bike.lol
That’s not to say that it wouldn’t be overheating in a deferent environment. Say tight woods at low speed or with mud caked on the cooling fins. With the type of riding I do I get good air flow so that helps I’m sure.

Maybe what I will do is keep stock studs and build myself a secondary oil cooler. I would rather spend $30 right now rather than $115 than may not be needed for 11:1 85.50 piston....The gaskets that come with the Wiseco Piston kit are for the xr400, so i will be getting a true 11:1 compression ratio...

[slightlybent47]

If it pretty hot out and I have been riding it hard, witch is 95% of the time; I will put a fan on it as soon as I bring her in for a landing and park it. A motor will continue to heat up for a minuet when you first shut them off. Water cooled motors have fans on them and a thermostat that will keep the fan on till it cools down.

[slightlybent47]

Originally posted by 400exmxrider15
Maybe what I will do is keep stock studs and build myself a secondary oil cooler. I would rather spend $30 right now rather than $115 than may not be needed for 11:1 85.50 piston....The gaskets that come with the Wiseco Piston kit are for the xr400, so i will be getting a true 11:1 compression ratio...

You’re doing less then I did and mine has run flawlessly for two + years. So I think studs is an option but not mandatory for your build.

[slightlybent47]

Maybe the ones that had trouble with them did not torque them correctly or the studs were not installed well in the first place. The guy that built mine told me if the weren’t done right you could have problems. He said to torque them in slow and small steps and do not over torque them. I got lucky or he was right cuz it’s still rippin.

Again if I was going with a bigger build I’d do the studs.

[400exmxrider15]

So running a Wiseco 11:1, Polished exhaust, bead blasted head and cylinder, SPAL fan on a custom secondary cooler...Yeah, I'm gonna be running C class this year...first year racing...I wont be nearly going as fast as you do...btw, I live in Southern Indiana, humid more than anything...the temp is like 90F on a June/July day, 98F on an august day, just feels like 110!!!

With running this high-comp piston, ive heard of jetting higher and running higher octane. I will be mixing 50/50 with 93 and 110 (renegade). I have a 168 main in it now, whats the next step up from that (Keihin jet)? My mods are in my signature. Thanks

[slightlybent47]

That sounds great, good luck this year, I hope you do well.
And yeah I hear ya on the heat. Now if I was doing a deferent kind of racing like hair scrambles where you ride for six hours through trails and mud at slow speeds under a heavy load then I’m sure I would have some heat issues. But for mx a spall fan and or the extra oil in the tank will do fine I think. Unless you’re an iron man or something.lol

[slightlybent47]

OH! and don't put yourself down, i'm not that fast!lol

[slightlybent47]

I just wanted you to know that I have had good luck with the way I did mine but you make your own decision.

[400exmxrider15]

Lol. I've been riding since i was 5 years old. This is the best machine I have ever ridden. I absolutely love it.

[slightlybent47]

Yeah, given all the bikes there are on the market and the pro’s and cons that go with them, the old ex is still hard to beat!